Quiet start to US tornado season

Figure 1 – Courtesy of NOAA

Although tornadoes can occur in any month of the year the ‘tornado season’ is usually thought of as being the months of March through to June, that’s when there’s a greater chance of cooler continental air meeting humid warmer air from the Gulf of Mexico, and hence a much greater chance of thunderstorm development. So far 2018 has been a remarkably quiet year for tornado activity across the United States (fig 1). In fact it could be that April 2018 has one of the lowest tornado counts on record (fig 2).

Figure 2

Here’s a news item from Matt Taylor of the BBC weather team about the slow start to the tornado season in the United States that spurred me into action (fig 2).